Cod sursa(job #2237244)

Utilizator parsulPaul Cristian Banu-Taran parsul Data 1 septembrie 2018 11:11:45
Problema Algoritmul Bellman-Ford Scor 35
Compilator cpp Status done
Runda Arhiva educationala Marime 1.39 kb
#include<iostream>
#include<fstream>
#include<vector>
#include<queue>
#define mp make_pair
#define NMAX 50001
#define oo 50000001
using namespace std;
ifstream in("bellmanford.in");
ofstream out("bellmanford.out");
int N,M,x,y,c,d[NMAX];
bool ok,viz[NMAX],inq[NMAX];
vector<pair<int,int> >matrix[NMAX];
queue<int>coada;
void initializare()
{
    int i;
    in>>N>>M;
    for(i=0;i<M;i++)
    {
        in>>x>>y>>c;
        matrix[x].push_back(make_pair(y,c));
    }
    for(i=1;i<=N;i++)
    {
        viz[i]=0;
        inq[i]=0;
        d[i]=oo;

    }
    coada.push(1);
    viz[1]=1;
    d[1]=0;
    inq[1]=1;
    ok=0;
}
void algoritm()
{
    while(!coada.empty()&!ok)
    {
        int ndcrt=coada.front();
        viz[ndcrt]++;
        if(viz[ndcrt]>=N)
            ok=1;
        inq[ndcrt]=0;
        coada.pop();
        for(int i=0;i<matrix[ndcrt].size();i++)
        {
            int neigh=matrix[ndcrt][i].first;
            int cost=matrix[ndcrt][i].second;
            if(cost+d[ndcrt]<d[neigh])
            {
               d[neigh]=cost+d[ndcrt];
               if(!inq[neigh])
                    coada.push(neigh);
            }
        }
    }
}
void tipar()
{
    if(!ok)
        for(int i=2;i<=N;i++)
        out<<d[i]<<" ";
    else
        out<<"Ciclu negativ!";
}
int main()
{
    initializare();
    algoritm();
    tipar();
}